• The Korean Journal of Ceramics
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• 제2권1호
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• pp.48-53
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• 1996

Ion beam assisted crystallization behavior of sol-gel derived $PbTiO_3$ thin films, deposited on bare silicon(100) substrates by spin-casting method, has been investigated. Ar ion bombardment was directly conducted on the spincoated film surface with or without heating the film from room temperature to $300^{\circ}C$. Ion dose was changed from $5{\times}10^{15}$ to $7.5{\times}10^{16}$ $Ar^-/cm^2$. Formation of (110) oriented perovskite phase was obseerved with ion dose above $5{\times}10^{16}\; Ar^+/cm^2$. Crystallization of $PbTiO_3$ thin film could be enhanced with increasing the Air ion dose, or heating the substrate during ion bombardment. Crystallization of the $PbTiO_3$ films by ion bombardment was related to the local heating effect during ion bombardment.

• 한국환경과학회지
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• 제7권5호
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• pp.697-705
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• 1998

$Pb^{2+}$ removal capacity and initial $Pb^{2+}$ removal rate were compared between non-biomaterials (granular activated carbon, powdered activated carbon, ion exchange resin, zeolite) and biomaterials (activated sludge, Aureobasidium pullulans, Saccharomyces cerevisiae). The $Pb^{2+}$ removal capacity of biomaterials were greater than that of non-biomaterials, generally. The $Pb^{2+}$ removal capacities of non-biomaterials and biomaterials were shown on the order of ion exchange resin ＞ zeolite ＞ granular activated carbon ＞ powdered activated carbon and A. pullulans ＞ S. cerevisiae ＞ activated sludge, respectively. In the initial $Pb^{2+}$ removal rate, the non-biomaterials showed powdered activated carbon ＞ granular activated carbon ＞ zeolite ＞ ion exchange resin and the biomaterials showed A. pullulans ＞ activated sludge ＞ S. cerevisiae. Comparing the $Pb^{2+}$ removal capacity and initial $Pb^{2+}$ removal rate of activated sludge with those of other non-biomaterials and biomaterials, activated sludge may have an availability on the removal of heavy metal ions by the economical and pratical aspects.

• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.123-130
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• 2019

We investigated the electrochemical behavior of an electrode coated with a nickel hexacyanoferrate/graphene oxide (NiPB/GO) composite to evaluate its potential use for the electrochemical separation of radioactive Cs as a promising approach for reducing secondary Cs waste after decontamination. The NiPB/GO-modified electrode showed electrochemically switched ion exchange capability with excellent selectivity for Cs over other alkali metals. Furthermore, the repetitive ion insertion and desertion test for assessing the electrode stability showed that the electrochemical ion exchange capacity of the NiPB/GO-modified electrode increased further with potential cycling in 1 M of $NaNO_3$. In particular, this electrochemical treatment enhanced Cs uptake by nearly two times compared to that of NiPB/GO and still retained the ion selectivity of NiPB, suggesting that the electrochemically treated NiPB/GO composite shows promise for nuclear wastewater treatment.

• 한국환경과학회지
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• 제9권4호
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• pp.325-330
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• 2000

The hydroxyapatite (HAp) for the present study was prepared by precipitation method in semiconductor fabrication and the crystallized at ambient to 95$0^{\circ}C$ for 30min in electric furnace. The ion-exchange characteristics of HAp for various heavy metal ions such as $Cd^{2+}, Cu^{2+}, Mn^{2+}, Zn^{2+}, Fe^{2+}, Pb^{2+}, Al^{3+}, and Cr^{6+}$ in aqueous solution has been investigated. The removal ratio of various metal ions for HAp were investigated with regard to reaction time, concentration of standard solution, amount of HAp and pH of solution. The order of the ions exchanged amount was as follws: $Pb^{2+}, Fe^{3+}>Cu^{2+}>Zn^{2+}>Al^{3+}>Cd^{2+}>Mn^{2+}>Cr^{6+}. The Pb^{2+}$ ion was readily removed by the Hap, even in the strongly acidic region. The maximum amount of the ion-exchange equilibrium for $Pb^{2+}$ ion was about 45 mg/gram of HAp. The HAp would seem to be possible agent for the removal of heavy metal ions in waste water by recycling of waste sludge in semiconductor fabrication.

• 한국결정성장학회지
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• 제8권2호
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• pp.307-314
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• 1998

졸-겔법을 이용하여 PZT박막을 제조하였다. 출발물질로는 Pb-acetate trihydrate, Zr-normal propoxide와 Ti-ispropoxide를 사용하였으며, 용매로는 2-Methoxyethanol과 iso- Propanol을 사용하였다. 기판에 따른 Pb 이온 및 Si 이온의 확산을 고찰하기 위해 bare Si와 열산화된 $SiO_2/Si$ 그리고 산화된 기판 위에 졸-겔 spin-coating법으로 $TiO_2$를 입힌 $TiO_2/SiO_2/Si$ 기판을 사용하였다. 박막의 치밀화 및 기판과의 접착상태는 SEM을 이용하였고, 상생성 온도는 XRD, 그리고 Pb 이온 및 Si 이온의 확산 정도는 ESCA를 사용하였다. 기판으로 bare Si 및 $SiO_2/Si$를 사용한 경우, $700^{\circ}C$에서 perovskite상을 얻을 수 있었으며, SiO2/Si 기판을 사용하여 Si의 막으로의 확산을 다소 방지할 수 있었다. $TiO_2/SiO_2/Si$기판을 사용한 경우, $500^{\circ}C$에서 perovskite상을 얻을 수 있었고, Pb 이온 및 Si 이온의 확산을 방지할 수 있었다.

• 한국세라믹학회지
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• 제29권4호
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• pp.259-264
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• 1992

The crystal structures and the bonding characteristics in $(Ba_xPb_{1-x})TiO_3$ have been investigated by X-ray diffraction analysis and infrared spectrophotometry. As $Ba^{2+}$ ion in $BaTiO_3$ were substituted by $Pb^{2+}$ ion, the structures were changed to orthorhombic from tetragonal, and also the covalent character in Ti-O bond increased, and then the dielectric constants decreased gradually. In the mixed oxide containing $Pb^{2+}$ ion more than 50%, the change-transfer energy of titanium ion increased.

• 대한화학회지
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• 제38권2호
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• pp.122-128
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• 1994

거대고리 리간드는 금속이온과 선택적으로 결합하는데, 이를 이용하여 에멀젼 액체막을 통한 금속이온의 이동에 관하여 연구를 수행하였다. 금속이온은 유기층에 있는 운반체에 의하여 source phase에서 recevinng phase으로 이동한다. 운반체로는 거대고리 리간드인 $DBN_3O_3$를 사용하였다. 여기에서 에멀젼 액체막을 통한 금속이온의 이동에 관한 요인과 어떤 금속이온의 선택적 분리에 관하여 검토하였다. 금속이온과 거대고리 리간드 그리고 금속이온과 recevinng phase내에 있는 음이온에 대한 안정도 상수를 금속이온의 선택적 이동에 대한 척도로 조사하였다. 납이온이 혼합 용액에서 다른 금속이온보다 높은 이동속도를 나타내었다. Recevinng phases내의 음이온이 금속이온의 이동에 중요한 역할을 한다.Recevinng phases내에 있는 $NO_3^-$을 $S_2O_3^{2-}$대치하면 이동량이 증가함을 보였는데 이는 $Pb^{2-}-S_2O_3^{2-}$상호작용이 $Pb^{2+}-NO_3^-$상호작용보다 크기 때문이다.

• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.538-542
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• 2007

Polymeric electrodes for lead ion based on N,N'-bis-thiophen-2-ylmethylene-pyridine-2,6-diamine as an ion carrier were prepared. The membrane electrode (m-3) containing o-NPOE as a plasticizer and 50 mol% additive of ionophore gives an excellent Nernstian response (29.59 mV/decade) and the limit of detection of ?log a (M) = 5.74 to Pb2+ in Pb(NO3)2 solution at room temperature. The prepared electrode provided good sensitivity and outstanding selectivity and response for Pb2+ over a wide variety of other metal ions in pH 7.0 buffer solutions. The good sensitivity and selectivity towards lead ion are attributed to the strong complexation of lead ion to N,N'-bis-thiophen-2-ylmethylene-pyridine-2,6-diamine which has geometrically the proper cavity to coordinate to the ligand.

• 한국세라믹학회지
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• 제33권7호
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• pp.743-754
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• 1996

In this study (Ba1-xPbx)TiO3 was synthesized by modified oxalate process in order to prevent vaporization of PbO through low temperature synthesis climinate Cl ion reproducibly substitute Pb for by and uniformly distribute ion (Ba1-xPbx)TiO3 was synthesized by coprecipitation of lead acetate barium acetate and ammonium titanyl oxalate have been used as starting materials. The substitution of Pb for Ba was reproducibly possible synthetic temperature of perovskite structure becomes lowed as the Pb concentration increases and fine partic-les (specific surface are :7.2 cm2/g) were obtained, BaTiO3 powders calcined at 90$0^{\circ}C$ for 3 hours were cubic from in XRD analysis and as Pb content was increases evident split of tetragonal peaks could be observed The optimum conditions to synthesize (Ba,Pb)TiO3 powder are the followings ; synthesis temperature (5$^{\circ}C$)

• 분석과학
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• 제15권2호
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• pp.163-171
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• 2002

수산가공 폐기물로 버려지는 게 껍질로부터 chitin을 추출하여 중금속 흡착제로 이용하였으며, 이 흡착제에 대해 Cd(II) 및 Pb(II) 이온의 흡착특성을 연구하였다. Chitin에 대한 Cd(II) 및 Pb(II) 이온의 흡착속도는 반응시간 2분경에 최대흡착량에 도달하였으며, 중금속 흡착에 미치는 pH의 영향은 두 이온 모두 pH 7.0>10.5>3.5순임을 알 수 있었다. Chitin에 대한 흡착률은 Cd(II)이온이 21${\sim}$99%이며, Pb(II)이온이 24${\sim}$95%이다. Cd(II)이온의 회수율은 22${\sim}$53%이고, Pb(II)이온의 회수율은 22${\sim}$73%로 나타났다. 이들 중금속 이온의 흡착양상은 Freundlich 흡착등온식에 비교적 잘 적용되었다.